9a I knew art in a way that could pull the wool over you (8)
KNITWEAR – An anagram (in a way) of I KNEW ART.

10a A seaman reported sudden violent attack (7)
ASSAULT – This is a homophone of A SALT (seaman), indicated by ‘reported’. Good surface reading for pirates – Aaargh!

11a Position from where Reds go for goals? (4,4)
LEFT WING – A good cryptic definition. Reds being left wing in the political sphere and a nod to Liverpool (well done you!) and/or Man United (Oops!) being known as the Reds. One of our NTSPP setters Hieroglyph came up with this anagram on Tuesday morning:
“Former Manchester United Manager David Moyes” anagram: “My! A tremendous move at Reds – man in charge fired!” Well done him!

12a Instrument finally played in fancy grooves (6)
FLUTED – Nicely misleading. Start with the FLUTE and then ad the last letter in (playe)D. I read this the other way round and got nowhere!.

22a At ball about two hours before midnight — in this? (10)
ATTENDANCE – Start with AT from the clue and add DANCE for ‘ball’. Then include (those letters are around/about the outside of) TEN which is two hours on the clock before midnight. A nice tricky clue!.

24a Snapper and artist arrived first (6)
CAMERA – A slightly chestnutty charade of CAME RA. The artist is the Royal Academicion and CAME (arrived) goes first.

25a One’s to be given run round in case (8)
CANISTER – I’S or ‘one’s’ with CANTER or run around the outside.

7d Contemplate not having time to be a go-between (7)
MEDIATE – This took a while for me to spot but is quite straightforward. Remove the T (not having Time) in MEDI(t)ATE or contemplate.

8d Essay about old play (7)
TRAGEDY – A TRY or essay around the outside of AGED/old.

11d Laird left a knight with state of depression (9)
LANDOWNER – L for Left, A from the clue then N for Knight (in chess notation – K is the King). Follow that with a DOWNER or state of depression in the vernacular.

14d Cleaner hit out, but not suspected (2,3,5)
IN THE CLEAR – An anagram (out again) of CLEANER HIT.

17d Marked in a playful way? (8)
DRAMATIC – A good cryptic definition with playful referring cryptically to the theatre.

18d Woolly ran if colour’s outside the visible spectrum (8)
INFRARED – Start with a woolly anagram of RAN IF then add RED for colour.